There are numerous industrial processes in which gas streams are produced containing CO.sub.2 as one of the components of the gas stream and in which it is desirable to selectively remove the CO.sub.2 from the other components. One technique used to selectively remove CO.sub.2 from process gas streams is to absorb the CO.sub.2 in an amine solution. Another technique used is to adsorb the CO.sub.2 on a molecular sieve.
The use of membranes to separate components in a process stream has long been pursued by the scientific and industrial community. Nonetheless, there remains a need for a membrane that has a high CO.sub.2 permeability and selectivity.
U.S. Ser. No. 499,267 (by this inventor) claims membranes comprising salts of aminoacids in hydrophilic polymers for removal of CO.sub.2 from gas streams containing CO.sub.2. That patent application does not cover the membrane compositions and polymer systems disclosed in the present invention. In addition, the membrane of the present invention with polyamine has outperformed that of the prior invention without polyamine.
It is an object of the present invention to provide novel polymer compositions that are suitable in formation of membranes useful in separating CO.sub.2 from process gases, particularly from a H.sub.2 rich gas stream containing CO.sub.2 and CO.